Compilation of materials for catalogues, books, newspapers or the like invariably involves trimming jobs, for example, trimming of an image on a photographic film or drawing to be fitted in a specified space or frame on a catalogue or the like. In such a case, it has been the usual practice to trim the object image into a square or rectangular shape conforming with the shape of the mounting space. This job is very troublesome and time-taking and requires meticulous skill. Therefore, there have been demands for development of a drafting or drawing implement which can facilitate the trimming jobs.